Machining centers are used for performing one or more of several operations on manufactured parts, such as drilling, grinding, cutting, etc. Machining centers can comprise, for example, an industrial machine tool attached to a rapidly rotating spindle. The tool, such as a drill, is attached to the spindle with conventional collet chuck or other similar attachment mechanism. The spindle is connected to a draw bar which extends through the spindle. Typically a drive belt and pulley assembly rotate the spindle tool and draw bar at high speeds. A channel may be provided in the draw bar to provide coolant to the tool. An example of a known machining center with a draw bar and spindle is shown in U.S. Pat. No. 5,022,278 to DeCaussin.
Machining centers that have a channel for coolant are known to have a problem with leakage of that coolant. It has been found that the coolant can spray across the interior of the machining center, requiring machine center down time, repair and service. It would be highly desirable to provide a machining center with improved draw bar alignment which reduces leaking of coolant fluid.